A longstanding problem with paint brushes that have fixed bristles that are used for industrial and domestic painting applications is that with time and repeated use, paint tends to build up within the bristles of the brush in the region where the bristles are held by the ferrule clamp that joins the bristles with the paint brush handle and base. The collected paint in this confined area is difficult to clean away. Usually, some residual paint is left in the bristles at the junction with the ferrule even after the used brush has been cleaned. The dried paint at this location collects and builds up over time with repeated use of the paint brush. This causes the bristles of the brush to spread and thereby reduces the efficiency of the brush. Also, the build up of dried paint tends to cause the bristles to wear and break at the location of the dried paint. This reduces the life of the paint brush.
Proper cleaning of a paint brush requires a considerable amount of solvent, if the person cleaning the brush is meticulous. If the paint has a water base, this is also a serious problem because large amounts of water are wasted attempting to thoroughly clean the brush. However, if the paint is an oil base paint, then expensive petroleum paint solvent or thinner is required for cleaning. The use of a petroleum base solvent constitutes a waste of costly solvent and at the same time creates an environmental pollutant. Most commercial painters will tend to minimize costs by balancing the amount of the solvent used with the number of times the paint brush is used. It may be economic, for instance, to only expect a paint brush to be used a half-dozen times before it must be discarded, rather than incur the cost and waste a considerable amount of solvent attempting to meticulously clean the brush after each use, and prolong the life of the paint brush.
A paint brush which minimizes or eliminates the build up of paint in the location where the bristles are set or meet the paint brush handle is desirable. Any invention which reduces the amount of solvent which is required to clean a paint brush is useful. It is also beneficial if a mechanism is used which reduces or eliminates bristle flare as it occurs over time when a paint brush is repeatedly used.
U.S. Pat. No. 5,289,606, Mar. 1, 1994, Blake A. Ledingham, discloses a unitary paint brush which comprises a paint brush body attached to a handle. The body defines a cavity adapted for receiving a group of bristles. A pair of hinged releasable flaps project over the cavity to abut the bristles when moved to a closed position. The bristles are released by moving the flaps into an open position. The hinged flaps are held in place on the bristle pack base by springs which can be rotated from a flap open position to a flap closed position, and vice versa. A problem with the springs is that they are a separate component from the body and raise manufacturing expense.
U.S. Pat. No. 5,315,733, May 31, 1994, Blake A. Ledingham, discloses a paint brush bristle clamp which can be removed after paint brush use, and facilitates cleaning of paint from the brush. The removable paint brush bristle clamp comprises: a pair of opposed end walls; a first side wall located between the pair of end walls and joined thereto; a second side wall opposed to the first side wall, the second side wall being joined at one end to one of the end walls, the opposite end of the second side wall being free and having a first lip formed thereon; and a second lip formed on one end of one of the end walls, adjacent to the lip formed on one edge of the adjacent side wall, said second lip being adapted to mate with the first lip on the side wall to thereby provide an opening and closing action.
U.S. Pat. No. 5,435,037, Jul. 25, 1995, Blake A. Ledingham, discloses a paint brush with a replaceable bristle pack. The unitary paint brush with replaceable bristles comprises: a paint brush body and handle, the body having formed in one end thereof opposite the handle a cavity adapted for receiving a group of bristles; at least one releasable member secured to one side of the paint brush body, and projecting over the cavity, the releasable member being capable of butting the bristles when moved to a first closed position, and being removed from the bristles when moved to a second open position; at least one movable securing member for securing the hinged releasable member in a first position and releasing the hinged releasable member for movement to a second open position; and a group of bristles held together and located within the cavity of the holder, and held in place by the hinged releasable member, said bristle group being removable and secured in place by the releasable member.
U.S. Pat. No. 4,129,918, Dec. 19, 1978, Robert Lee, discloses an adjustable sleeve for an artist's paint brush adapted to adjust the effective length of the bristles of the brush. The adjustable sleeve is tubular at its tip to contain the hair or bristles. The sleeve is split above the tip to provide a spring biased grip upon the brush ferrule. The adjustable sleeve is tapered in substantial conformity with the taper of the ferrule and it is longitudinally adjustable relative to the ferrule to vary the effective length of the hair or bristles. The sleeve is designed for use with an artist's brush, which has bristles arranged in a taper column form. The sleeve does not fit over the base of the brush at the location where the bristles meet the base.
U.S. Pat. No. 4,237,579, Dec. 9, 1980, Jonathan H. Salmon, discloses a tool for applying a liquid stain to a flat surface to impart a timber grain effect to the surface. The tool comprises a paint brush, a bristle retaining slidable plate on one side of the brush and a slidable comb plate on the other side of the brush. Both of the plates have an elongated slot which engages a bolt which passes through the paint brush. The comb adjustably separates the brush bristles into discrete bunches to permit the application of stain to impart a wood grain pattern to the surface. This tool does not disclose a holder which fits on both sides of the paint brush base where the bristles are secured to the base. The tool is not designed to prevent paint from migrating down the bristles in the direction of the base.
U.S. Pat. No. 4,339,837, Jul. 20, 1982, Christiaan Reeberg, discloses a sliding box-like girdle which fits over a paint brush to confine the bristles. The girdle acts as a hanger so that the paint brush can be hung on a wall. The girdle also protects the brush bristles while on display, or during storage. Further, the girdle is used to control the effective length of the bristle ends for specific painting jobs. The girdle also serves to squeeze excess paint from the bristles after each dip into a can of paint. The girdle does not serve to encircle the base of the paint brush, where the bristles meet the paint base, and thereby prevent paint from migrating along the bristles to the base, and thereby collecting at the base-bristle ended face.
French Patent. No. 714,282, Deroubaix et al., published Nov. 10, 1931, discloses a paint brush with a removable bristle pack, a hinged panel 5 which, in a closed position, grips the bristles 7, and a ring 8 which encloses the bristles 7. The ring 8 can possibly be interpreted as an internal ferrule. However, the ring 8 has no ridges that fit within grooves inside the cavity. Also, Deroubaix et al. use a sliding ring 9 which can be moved up once the panel 5 is closed in order to hold the brush together (see FIG. 4).